Demand for Ruby, Hadoop and HTML5 developers jumped this year, with jobs requiring those skills increasing 70 per cent compared to the same period in 2010, according to a survey of the tech jobs in London by recruiters Adzuna. Adzuna collated every tech job advertised for London last month, a total of 100,000. HTML coders are still the most in demand, but also the most poorly paid – both at entry and top levels.

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You don't need to be a genius to debug a pf.conf firewall ruleset, you just need the guts to run tcpdump